What is Biomass?
Biomass is organic material (Plant or animal matter) which may be used for producing energy or in many industrial processes as a raw material.
Hence, biomass examples include organic matter including wood and other forest products, waste materials from harvesting food crops, horticulture, food processing, animal farming. Even human waste from wastewater plants.
There are 3 types of biomass materials:
The method of obtaining energy from biomass fuels depends upon the type of biomass being used.
- Natural: Biomass which is produced without any human intervention.
- Energy crops: These types of plants are specifically grown to obtain biomass energy from them. They are usually grown in large numbers.
- Waste Materials: This type of biomass consists of the remains and waste products from various industries and farming processes. Examples of this would be olive pits, corn stover or almond shells.
What is Biomass Energy?
The chemical compounds inside organic matter possess energy within their bonds which are broken when the plant or animal needs that energy or if it is burned.
Breaking of those chemical bonds in Biomass releases heat energy. This process can be manipulated in such a way so that organic matter can be used directly or in the form of biofuel to produce Biomass energy.
Biomass is a renewable source of energy as opposed to the limited fossil fuels. Along with solar energy, hydropower and wind energy; biomass energy is also considered as one of the most important alternatives to fossil fuels.
As a society, we are in desperate need for sustainable forms of energy and that is why we make use of chemical energy to produce heat energy or electricity.
Types of Biomass, Bio-fuel and its uses
All types of wood can be used to produce energy. For example; sawdust, wood-chips, wood pellets and logs. There are multiple ways to obtain energy from wood biomass.
1. Wood combustion:
The process of burning wood to release energy is well known in history as well as in today’s modern world. The process involves burning wood in any form.
Burning wood releases heat energy which is used to heat up water in a boiler or a tank. The water boils and releases steam which spins the turbine and pushes the generator to produce electricity. Wood combustion to generate electricity for industrial processes is mostly done by the forestry industry.
Co-generation is defined as generating electricity as well as heat energy. This system requires heavy investment but on the same side it has a higher efficiency (85%) when compared with wood combustion (55%). With Co-generation, there is a net reduction in greenhouse gasses, carbon footprint, air and water pollution.
3. Wood Gasification
This process involves heating wood at high temperatures in a chamber with small amounts of oxygen. Hydrogen and carbon monoxide are released from wood as they are pyrolysis gases.
These gases can further be mixed with oxygen to produce heat.Just like other methods, this heat is used for the boiler to make steam, spin the turbines and make electricity.
This plant-based biomass includes energy crops as well as biological residue from farming processes. The biological matter is burned to produce heat which heats up the boiler.
Just like previous methods, the steam is used to spin the turbine and power the generator which produces electricity. The process of electrcity generation is quite similar to wood processes; the difference is in the type of biomass and it’s uses thereafter.
Farmers can use their own waste to produce energy required by the farm itself. This would have many benefits including reduced costs, better efficiency and before i forget, a self-sustaining farm.
Excess garbage disposal has been causing problems all over the world . It is time that we put it to good use, like generating electricity. This has been put into practice in several countries including Sweden, Norway, Denmark, United Kingdom and The United States .
The garbage is burned to produce heat energy. The process of electricity generation is the same; heating up boilers to produce steam, spin turbines and push the generator.
However, there is a slight difference. The solid waste is not biomass alone.16% of total garbage from towns is plastic, which is a petroleum product. If the plastic was not separated and the waste was burned directly; a huge load of toxic air pollutants would be released into the atmosphere.
When fungi and bacteria feed on dead organic matter, they produce biogas. Biogas consists of different gases and one of them includes methane. The methane gas can be used to produce heat energy since it is flammable.
Decomposing animal waste also generates methane gas which is harmful for the environment because it is a greenhouse gas.
Industrial farming has increased a lot over the years and so have methane gas emissions. To reduce this environmental footprint, governments have introduced laws which direct the owners of industrial farms to gather waste materials of animals in containers named as digesters. These digesters are connected to a piping system directed towards an electricity generation plant.
This makes sure that methane is put to good use rather than harming the atmosphere.
These are deposit sites for waste material to be dumped underground. This method of waste disposal has been used to get rid of waste for many years.
However, over the years, people realised that methane/biogas released from these landfills can also be put to good use like generating electricity.
The process involves a piping system to extract the gas from the landfill and take it to a nearby power plant. The gas is then used as fuel for running boilers, producing steam, spinning turbines and generating electricity.
You may think that this sector is not popular; But in 2003, 33% of the UK’s renewable energy was produced from landfills.
There are four alcohols which can be used as an alternative to conventional fuel. These include butanol, ethanol, propanol and methanol. Ethanol is the most accessible out of all these.
Since ethanol is made from plant-based materials, it is produced in large quantities. The plants used in making ethanol are used to extract sugars and starches which ferment and produce ethanol after distillation. Ethanol can be produced by any plant which contains cellulose and sugar. Ethanol is flammable which is why it can be used as fuel.
Newer car engines have the ability to withstand up to 15% ethanol in fuel and such fuel is named E15. E-15 is actually considered high quality and high-octane fuel when compared to conventional gas.
Biodiesel is also an alternative to fuel, and a very important one. It is made from oils such as vegetable oil and animal oil. The most important source of biodiesel is the recycled oil obtained from restaurants. Many of the engines produced nowadays support biodiesel without any modifications. This makes them one of the best alternatives of fuel.
How does Biomass Energy work?
It is very important to understand how biomass actually works to produce energy. We’ll start by how chemical energy is produced in plants.
First step in making Biomass is Photosynthesis, an important process for plants to make their own food in the form of chemical compounds. The plants are able to use solar energy to convert CO2 and H2O into chemical energy in the form of different compounds like carbohydrates.
These chemical compounds possess energy within their bonds and release that energy when the plants need it or an animal who ate the plant needs it.
We burn (ignite) the organic matter which gives enough energy to trigger a reaction converting biomass into heat energy and atmospheric gasses. The heat energy released from this reaction can be used in place of methane or it can be used as fuel for boilers in power plants, and numerous other uses we’ve discussed already.
Fossil fuels have a similar way of releasing energy when they are burnt. The main difference between Biomass and Fossil fuels is that Biomass produces energy from living or recently-dead organisms, whereas Fossil Fuels produce energy from biological material that absorbed CO2 from the atmosphere millions of years ago.